Dry photoresist stripping process and apparatus

Abstract

A process for stripping photoresist from a substrate is provided. A processing system for implanting a dopant into a layer of a film stack, annealing the stripped film stack, and stripping the implanted film stack is also provided. When high dopant concentrations are implanted into a photoresist layer, a crust layer may form on the surface of the photoresist layer that may not be easily removed. The methods described herein are effective for removing a photoresist layer having such a crust on its surface.

1 . A photoresist stripping method, comprising:
 positioning a substrate having a photoresist layer thereon in a stripping chamber;   forming a plasma from hydrogen gas and at least one of fluorine gas and oxygen gas in a remote plasma source;   introducing plasma from the remote plasma source and water vapor to the chamber; and   stripping the photoresist from the substrate.   
   
   
       2 . The method of  claim 1 , wherein the photoresist layer is exposed to an implanting process prior to stripping. 
   
   
       3 . The method of  claim 1 , further comprising:
 annealing the stripped substrate.   
   
   
       4 . The method of  claim 1 , further comprising:
 disposing the substrate having the photoresist into an implantation chamber, implanting ions into a layer disposed between the substrate and the photoresist layer, and forming a crust layer on the photoresist;   transferring the substrate from the implantation chamber;   transferring the substrate from the stripping chamber into an annealing chamber; and   annealing the substrate.   
   
   
       5 . The method of  claim 4 , wherein the ions are selected from the group consisting of boron, phosphorus, arsenic, and combinations thereof. 
   
   
       6 . The method of  claim 4 , wherein the crust layer comprises two aromatic rings bonded together by two single carbon-carbon bonds. 
   
   
       7 . The method of  claim 1 , wherein the stripping comprises converting the photoresist into diatomic oxygen, carbon dioxide, water, and diatomic hydrogen. 
   
   
       8 . The method of  claim 1 , wherein the stripping further comprises biasing the substrate with an RF current. 
   
   
       9 . A photoresist stripping method, comprising:
 disposing a substrate into processing chamber, the substrate having a photoresist layer thereover;   implanting one or more ions into a layer disposed between the photoresist and the substrate, the implanting forming a crust layer out of at least a portion of the photoresist layer;   igniting a plasma in a remote plasma source and exposing the crust layer to the plasma;   exposing the crust layer to water vapor; and   removing the crust layer and the photoresist layer.   
   
   
       10 . The method of  claim 9 , wherein the crust layer comprises two aromatic rings bonded together by two single carbon-carbon bonds. 
   
   
       11 . The method of  claim 9 , wherein the implanted ions comprise boron and the plasma is ignited by flowing hydrogen gas through the remote plasma source. 
   
   
       12 . The method of  claim 11 , wherein the water vapor has a flow rate of between about 80 sccm to about 100 sccm. 
   
   
       13 . The method of  claim 11 , wherein the water vapor has a flow rate of between about 2800 sccm to about 3000 sccm. 
   
   
       14 . The method of  claim 9 , wherein the implanted ions comprise boron and the plasma is ignited by flowing carbon tetrafluoride and oxygen through the remote. plasma source. 
   
   
       15 . The method of  claim 14 , wherein the carbon tetrafluoride has a flow rate between about 225 sccm and about 275 sccm, the oxygen has a flow rate between about 4900 sccm and about 5100 sccm, and the water vapor has a flow rate between about 325 sccm and about 375 sccm. 
   
   
       16 . The method of  claim 9 , wherein the ions are selected from the group consisting of boron, phosphorus, arsenic, and combinations thereof. 
   
   
       17 . The method of  claim 9 , wherein the stripping comprises converting the photoresist into diatomic oxygen, carbon dioxide, water, and diatomic hydrogen. 
   
   
       18 . The method of  claim 9 , further comprising annealing the substrate. 
   
   
       19 . A processing system, comprising:
 a transfer chamber;   an implantation chamber coupled with the transfer chamber;   a stripping chamber coupled with the transfer chamber;   an annealing chamber coupled with the transfer chamber;   a factory interface coupled with the transfer chamber; and   one or more FOUPs coupled to the factory interface.   
   
   
       20 . The system of  claim 19 , wherein the stripping chamber comprises a remote plasma source coupled thereto.